A cylinder valve for use with a cylinder containing fluid under pressure includes a valve body configured for releasable connection to the cylinder. The opposite ends of the resonator, the mode-locking element and the solid-state laser medium are disposed to provide an average beam diameter of lasing light of not more than 150 \u03bcm on the mode-locking element and an average beam diameter of the lasing light of not more than 200 \u03bcm within the solid-state laser medium. LED lights displayed on the housing may be of different colors and may be arranged in a multitude of ways.